Chilli anthracnose disease caused by Colletotrichum species

Anthracnose disease is one of the major economic constraints to chilli production worldwide, especially in tropical and subtropical regions. Accurate taxonomic information is necessary for effective disease control management. In the Colletotrichum patho-system, different Colletotrichum species can be associated with anthracnose of the same host. Little information is known concerning the interactions of the species associated with the chilli anthracnose although several Colletotrichum species have been reported as causal agents of chilli anthracnose disease worldwide. The ambiguous taxonomic status of Colletotrichum species has resulted in inaccurate identification which may cause practical problems in plant breeding and disease management. Although the management and control of anthracnose disease are still being extensively researched, commercial cultivars of Capsicum annuum that are resistant to the pathogens that cause chilli anthracnose have not yet been developed. This paper reviews the causal agents of chilli anthracnose, the disease cycle, conventional methods in identification of the pathogen and molecular approaches that have been used for the identification of Colletotrichum species. Pathogenetic variation and population structure of the causal agents of chilli anthracnose along with the current taxonomic status of Colletotrichum species are discussed. Future developments leading to the disease management strategies are suggested.      

Identification of Colletotrichum spp. isolated from strawberry in Zhejiang Province and Shanghai City, China

Strawberry anthracnose, caused by Colletotrichum spp., is a major disease of cultivated strawberry. This study identifies 31 isolates of Colletotrichum spp. which cause strawberry anthracnose in Zhejiang Province and Shanghai City, China. Eleven isolates were identified as C. acutatum, 10 as C. gloeosporioides and 10 as C. fragariae based on morphological characteristics, phylogenetic and sequence analyses. Species-specific polymerase chain reaction (PCR) and enzyme digestion further confirmed the identific...     

Effects of rhizobacteria <Emphasis Type="Italic">Paenibacillus polymyxa</Emphasis> APEC136 and <Emphasis Type="Italic">Bacillus subtilis</Emphasis> APEC170 on biocontrol of postharvest pathogens of apple fruits

In this study, plant growth-promoting rhizobacteria (PGPR) were evaluated as potential biocontrol agents against postharvest pathogens of apple fruits. In vitro bioassays revealed that, out of 30 isolates screened, isolates APEC136 and APEC170 had the most significant inhibitory effects against the mycelial growth of several fungal pathogens. Analysis of 16S ribosomal RNA (rRNA) sequences identified the two effective isolates as Paenibacillus polymyxa and Bacillus subtilis, respectively. The two strains showed greater growth in brain-heart infusion broth than in other growth media. Treatment of harvested apples with suspensions of either strain reduced the symptoms of anthracnose disease caused by two fungal pathogens, Colletotrichum gloeosporioides and Colletotrichum acutatum, and white rot disease caused by Botryosphaeria dothidea. Increased productions of amylase and protease by APEC136, and increased productions of chitinase, amylase, and protease by APEC170 might have been responsible for inhibiting mycelial growth. The isolates caused a greater reduction in the growth of white rot than of anthracnose. These results indicate that the isolates APEC136 and APEC170 are promising agents for the biocontrol of anthracnose and white rot diseases in apples after harvest, and suggest that these isolates may be useful in controlling these diseases under field conditions.     

炭疽菌的遗传转化及应用研究进展

由炭疽菌属（Colletotrichum cda．）真菌引起的植物炭疽病在生产上危害严重,近年来,炭疽菌转化技术的发展为全面研究该菌的致病机理及炭疽病防治奠定了良好的技术基础。本文重点介绍了炭疽菌的转化方法及在致病机理、致病相关基因克隆和病害防治等研究领域的应用。     

葡萄黑痘病发生因素分析及综合治理

种植大量的单一感病品种、连续不断的降雨是葡萄黑痘病大流行的主要因素，田园管理不善，杂草丛生、化学防治效果差是黑痘病流行的次要因素。本文结合黑痘病的发生因素分析，制定了相应的综合防治措施。     

辣椒炭疽病原菌生物学特性研究

对炭疽病典型症状的辣椒果实进行分离纯化获得炭疽病原菌,诱导产孢进行形态学鉴定,在不同温度、光照、培养基成分等条件下对该病原菌生物学特性进行研究。结果表明,诱导产孢进行形态学鉴定该病原菌为胶孢炭疽菌(Colletotrichum gloeosporioides);菌丝生长的最适温度为25~30℃;菌丝正常生长不受光照条件影响;菌丝的生长受大蒜和芥菜中的某些成份的抑制。该研究以期为辣椒病害防治以及品质的提高提供理论依据。     

柑橘炭疽病研究现状与展望

柑橘炭疽病是一种常见的,为害较为严重的真菌性病害,其病原菌是Colletotrichum gloeosporioides Penz.柑橘炭疽病一般在夏秋季节,高温多雨的条件下较容易发病.目前对柑橘炭疽病的防治方法主要是进行合理的田间管理和使用合适的化学农药.本文基于近期关于柑橘炭疽病的研究报道,对柑橘炭疽病的病症及为害、病原体、发病规律、防治等几个方面进行了系统的综述.对近期柑橘炭疽病的研究成果进行了简要的小结,提出了今后柑橘炭疽病研究中需要解决的问题及其发展趋势.     

连云港(前三岛)“吸血蝇”的鉴定研究

近年来,在连云港前三岛发现一数量极多、危害严重的“吸血蝇”。经鉴定为厩螫蝇Stomoxys calcitrans(Linnaeus,1758).属蝇科Muscidae、螫蝇属Stomoxys Geoffroy.据文献记载,该蝇不仅吸食人、畜血液,还会传播炭疽病等多种传染病。本文在综述的基础上将对其生活习性、分布、生活史等做进一步研究,旨在提出防治和控制措施。     

Contiguity and covariation in human causal inference

Nearly every theory of causal induction assumes that the existence and strength of causal relations needs to be inferred from observational data in the form of covariations. The last few decades have seen much controversy over exactly how covariations license causal conjectures. One consequence of this debate is that causal induction research has taken for granted that covariation information is readily available to reasoners. This perspective is reflected in typical experimental designs, which either employ covariation information in summary format or present participants with clearly marked discrete learning trials. I argue that such experimental designs oversimplify the problem of causal induction. Real-world contexts rarely are structured so neatly; rather, the decision about whether a cause and effect co-occurred on a given occasion constitutes a key element of the inductive process. This article will review how the event-parsing aspect of causal induction has been and could be addressed in associative learning and causal power theories.     

Nonnormative discounting: There is more to cue interaction effects than controlling for alternative causes

Several experiments on human causal reasoning have demonstrated “discounting”-that the presence of a strong alternative cause may decrease the perceived efficacy of a moderate target cause. Some, but not all, of these effects have been shown to be attributable to subjects’ use of conditional rather than unconditional contingencies (i.e., subjects control for alternative causes). We review experimental results that do not conform to the conditionalizing contingency account of causal judgment. In four experiments, we demonstrate that there is “nonnormative discounting” above what is accounted for by conditionalization, that discounting may depend on the nature of the question put to the subjects, and that discounting can be affected by motivation. We conclude that because nonnormative discounting occurs for summary presentations as well as trial-by-trial presentations of information and because nonnormative discounting depends on motivation, it is not a necessary result of cue competition during the contingency learning process.     

Does more schooling improve health outcomes and health related behaviors? Evidence from U.K. twins

Several recent studies using instrumental variables based on changes in compulsory school-leaving age laws have estimated the causal effect of schooling on health outcomes and health-related behaviors in the U.K. Despite using the same identification strategy and similar datasets, no consensus has been reached. We contribute to the literature by providing results for the U.K. using a different research design and a different dataset. Specifically, we estimate the effect of schooling on health outcomes (obesity and physical health) and health-related behaviors (smoking, alcohol consumption and exercise) for women through within-MZ twins estimates using the TwinsUK database. For physical health, alcohol consumption and exercise, the within-MZ twins estimates are uninformative about whether there is a causal effect. However, we find (1) that the significant association between schooling and smoking status is due to unobserved endowments that are correlated with schooling and smoking and (2) there is some indication that more schooling reduces the body mass index for women, even once these unobserved endowments have been controlled for.     

Collaborative processes in species identification using an internet-based taxonomic resource

Visual databases are increasingly important resources through which individuals and groups can undertake species identification. This paper reports research on the collaborative processes undertaken by pre-service teacher students when working in small groups to identify birds using an Internet-based taxonomic resource. The student groups are conceptualised as ‘knowledge-building communities’ working in a ‘joint problem space’ comprising the collective knowledge of the participants interacting with the taxonomic database. Collaborative group work and associated dialogue were recorded with digital video. The recordings were analysed for the categories of dialogue and the categories of knowledge used by the students as they interacted with the taxonomic database and how they drew on their previous experiences of identifying birds. The outcomes are discussed in the context of the interplay of individual and social processes and the interplay between abstraction and lived experience in the joint problem space.     

对高校学籍信息化管理的初步探讨

高校学籍管理越来越受到国家教育部和各高等院校的重视。随着办学规模的扩大、专业设置和学生人数的增加,原有的学籍管理方法已不适应高校发展的要求。而网络学籍管理系统从学生入校、在校期间到毕业发证全过程实现了"一条龙"的信息化管理。     

做合格的国际汉语教师 积极弘扬中华优秀文化

中国经济发展取得了举世瞩目的成就,中国的国际地位和影响力不断提高和上升,中国政府积极主导并支持国际合作办学。在这样的背景下,做一名合格的国际汉语教师要有实现中国梦的责任感和使命感,要具备语言和教学能力、外语和交际能力、组织和管理能力。国际汉语教师肩负着开展公共外交和提升中国文化软实力的重任,要能够运用现代信息技术进行国际汉语教学。     

昆明烟区红花大金元黑胫病样症状致病原的鉴定及防治方法探索

在昆明烟区5个红花大金元种植点选取具有典型黑胫病症状的烟样16个,采用组织分离法分离、燕麦培养基培养和光学显微镜鉴定,结果表明,在昆明地区发生黑胫病样症状的病株,不一定都仅仅是感染黑胫病病原菌,既有单一病原菌感染的典型黑胫病,也有黑胫病伴随的根黑腐病,还有可能是发生了立枯病、根黑腐病或是其他病原菌感染,其中有的是单一病原危害造成、有的是2~3种病菌混生导致.因此,根据烟草黑胫病样病害发病条件、发病规律,结合当前的防治药剂,建议制定以病原菌鉴定为依据,采取农业防治、生物防治和化学防治相结合的综合防治措施则可得到切实的防治.     

信息不对称下的高校学籍学历管理问题研究

作为现代信息经济学重要研究内容的信息不对称现象,毫不例外地存在于高校学籍学历管理之中。运用信息不对称理论,分析高校学籍学历管理中存在的种种信息不对称现象,分析其存在成因既有普遍原因,也有基于学籍学历管理本身的特殊原因。应当在发挥行政部门强制作用、完善电子注册制度的同时,通过理顺管理体制、畅通管理渠道、应用现代技术、降低...     

Partial Identification of Answer Reviewing Effects in Multiple-Choice Exams

Does reviewing previous answers during multiple-choice exams help examinees increase their final score? This article formalizes the question using a rigorous causal framework, the potential outcomes framework. Viewing examinees’ reviewing status as a treatment and their final score as an outcome, the article first explains the challenges of identifying the causal effect of answer reviewing in regular exam-taking settings. In addition to the incapability of randomizing the treatment selection (reviewing status) and the lack of other information to make this selection process ignorable, the treatment variable itself is not fully known to researchers. Looking at examinees’ answer sheet data, it is unclear whether an examinee who did not change his or her answer on a specific item reviewed it but retained the initial answer (treatment condition) or chose not to review it (control condition). Despite such challenges, however, the article develops partial identification strategies and shows that the sign of the answer reviewing effect can be reasonably inferred. By analyzing a statewide math assessment data set, the article finds that reviewing initial answers is generally beneficial for examinees.     

试论体育赛事对举办地的综合性影响

摘要：当今世界的全球化趋势，使每个国家和地区都无法避免地被卷入了以经济竞争为特征的竞争强迫状态，城市在更大的空间尺度上面，临着更多的机遇和挑战，在信息、交通等新科技革命的推动下，资本、信息、技术等资源在全球范围内加速流动，并促使了相互依赖、相互作用的世界城市网络的形成，各城市为了提升自身在世界城市网络中的地位，为尽可能多地获得经济发展的资源而展开了激烈的竞争。与此同时，世界范围的全球竞争与资本流动导致了地方主义的兴起，迫使城市和区域普遍关心地方的发展，注重不同形式的城市和区域的重构。     

Detecting blickets: how young children use information about novel causal powers in categorization and induction

Three studies explored whether and when children could categorize objects on the basis of a novel underlying causal power. To test this we constructed a "blicket detector," a machine that lit up and played music when certain objects were placed on it. First, 2-, 3- and 4-year-old children saw that an object labeled as a "blicket" would set off the machine. In a categorization task, other objects were demonstrated on the machine. Some set it off and some did not. Children were asked to say which objects were "blickets." In an induction task, other objects were or were not labeled as "blickets." Children had to predict which objects would have the causal power to set off the machine. The causal power could conflict with perceptual properties of the object, such as color and shape. In an association task the object was associated with the machine's lighting up but did not cause it to light up. Even the youngest children sometimes used the causal power to determine the object's name rather than using its perceptual properties and sometimes used the object's name rather than its perceptual properties to predict the object's causal powers. Children rarely categorized the object on the basis of the associated event. Young children also sometimes made interesting memory errors-they incorrectly reported that objects with the same perceptual features had had the same causal power. These studies demonstrate that even very young children will easily and swiftly learn about a new causal power of an object and spontaneously use that information in classifying and naming the object.